Concrete-reinforcing bar.



W. P. MULLANE & W. WUTHENOWP CONCRETE REINFOBCING BAR. APPLICATION FILED OCT. 4. m6.-

Lwgfigu mmmdl NOV 2?, 191?.

WILLIAM PATRICK I/IIJ'LLANE, 0F MOLINE, AND WILLIAM WUTHENOVT, OF CHICAGO, ILLINOIS.

CONCRETE-REINFORCING BAR.

Specification of Letters Patent.

Patented Nov. 2?, 121?.

Application filed October 4, 1916. Serial No. 123,653.

To all whom it may concern:

Be it known that we, VVILLIAM PATRICK MULLANE and WILLIAM l/VUTHnNow, citizens of the United States, residing at Moline, in the county of Rock Island and State of Illinois, and Chicago, Cook county, Illinois, respectively, have invented a certain new and useful Improvement in Concrete Reinforcing Bars, of which the following is a full, clear, concise, and eXact description, reference being'had to the accompanying drawings, forming a part of this specificatlon.

This invention relates to improvements in concrete reinforcing bars.

The object of the invention is to provide a bar suitable for use in reinforced con crete and other similar built up structures, the bar being so designed that it may be easily and cheaply rolled and of such con struction that the neutral axis of the beam,

or slab in which the bar is used, may be lowered.

Another and more specific object of the invention is to provide a reinforcing bar for use in concrete structures so designed that less metal for the same strength is required or greater strength is obtained by the use of the same amount of metal as now employed.

In the drawing forming a part of this specification, Figure 1 is a bottom plan view of a portion of a reinforcing bar embodying our improvements. Figs. 2 and 3 are opposite side elevations of the improved bar. And Figs. 4:, 5 and 6 are cross sectional views of the improved bar taken respectively on the lines H, 5--5, and 66 of Figs. 2 and 3.

In said drawing, the improved bar is designated generally by the reference A and, as shown, is of substantially equilateral triangular cross section having a lower horizontal face 10, and upwardly inclined side faces 11 and 12. The side faces 11 and 12 are provided with ribs 13 and 14, respectively, the ribs 13 being arranged parallel to each other and extending at a diagonal to the length of the bar. The ribs 14: are also arranged parallel to each other and extend diagonally'to the length of the bar but in the opposite direction to the ribs 13. Each of the ribs 13 and 14 is substantially of trapezoidal cross section, as

clearly illustrated in Figs. l, 5 and 6. The ribs 13 and 1% are also tapered at their ends as indicated at 15. The ribs 13 overlap each other, as clearly illustrated in Fig. 3, a vertical plane passing through the bar at the tip of one of the ribs intersecting the overlapping rib at a pointwhere the taper commences, the design being such that any vertical section through the bar will have the same amount of metal. That is, a vertical section passing through the bar so as to intersect but one rib 13 will show the maximum section of said rib. When taken in a vertical plane intersecting two of the ribs 13, the section of one rib will decrease in proportion to the increase in section of the opposite tapered end of theoverlapping rib 13. The same arrangement and formation of the ribs 1% is employed on the other face 12 of the bar, and the sets of ribs 13 and 1d are so disposed longitudinally of the bar that a vertical section of the bar at any point in the length thereof will always have the same cross sectional area. By arranging the ribs 13 and 14 as above described, it will be noted that the tendency of the concrete to move the bar lengthwise is neutralized by the oppositely arranged ribs 13 and 14:. Furthermore, by having the passageways between the ribs 13 and 14k open at the top and bottom, trapping of air or water is prevented but at the same time the inclination of the ribs is such as to prevent passage of the concrete thcrethrough.

The bottom face 10 of the bar is provided with a centrally located continuous, longitudinally extending rib 18 of uniform cross section throughout, said rib 18 being also of trapezoidal cross section. As will be understood by those skilled in the art, the rib 18 effectively prevents slipping of the bar laterally in the concrete or other building material in which it is embedded.

By the triangular formation of the bar with the apex of the triangle at the top, and the use of the longitudinally extending rib 18 at the bottom thereof, it is apparent that the metal in the bar is concentrated near the bottom thereof so that when the bar is used in a slab or beam, the neutral axis thereof is lowered as compared with other types of reenforcing bars now in use. By this means, we are enabled to employ less metal in the bars for structures of the same strength, as

will be understood by those skilled in the art. The bar may be manufactured by rolling, as will be apparent.

Although we have herein shown and described what we now consider the preferred embodiment of our invention, the same is merely illustrative and we contemplate all changes that come within the scope of the claims appended hereto.

lVe claim 1. A metal reinforcing bar adapted for use in concrete construction such as slabs, or beams, the bar being of substantially triangular cross section with flat faces and provided with a longitudinally extending rib along the bottom face thereof, whereby the neutral axis is lowered.

2. A metal reinforcing bar adapted for use in concrete construction such as slabs, or beams, the bar being of substantially triangular cross section, the two upper sides thereof being provided with ribs extending diagonally to the length of the bar, the bottom face of the bar being provided with a longitudinally extending rib.

3. A metal reinforcing bar of the character described, said bar being of substantially triangular cross section with one face arranged horizontally, the two inclined faces being provided with ribs disposed diagonally to the length of the bar, the ribs on one side extending oppositely to the ribs on the other side, to thereby prevent longitudinal shifting of the bar, the bottom face of the bar being provided with a longitudinally extending rib to thereby lower the neutral axis of the bar.

fiopies of this patent may he obtained for five cents each, by addressing Washington, D. 0.

4. A metal reinforcing bar of the character described, said bar being of substantially triangular cross section and provided with diagonally extending ribs on two of its sides, each of said ribs being of substantially the same cross sectional area throughout its length except at its ends, the ribs on the same side overlapping each other at their ends, said bar having a longitudinally extending rib on the third side, all of said ribs being so arranged that the cross sectional areas of the bar. at all points thereonare equal.

5. A metal reinforcing bar of the character described, the bar being polygonal in cross section with fiat faces and having diagonally arranged ribs on two sides thereof and a longitudinally extending rib on another side thereof, said diagonally arranged ribs being tapered at their ends,,all of said the purpose specified.

lVILLI-AM PATRICK MULLANE. WVILLIAM lVUTHENOlV.

the "Commissioner 0f Patent 

